Conventional compact motor-compressors that incorporate compressors directly coupled with high-speed electric motors have been developed and may often be utilized in a myriad of industrial processes (e.g., petroleum refineries, offshore oil production platforms, and subsea process control systems) to compress process fluids. The compact motor-compressors may combine the high-speed electric motors with the compressors, such as a centrifugal compressor, in a single, hermetically-sealed housing. Through shared or coupled rotary shafts supported by a bearing system, the motors may drive or rotate the compressors to thereby compress the process fluids.
As the motors drive the compressors, heat may be generated by electrical systems configured to deliver electrical energy to stators of the motors. Additional heat may also be generated through windage friction resulting from the rotating components operating in the pressurized process fluids. Improper management of the heat may reduce operational efficiencies and may ultimately result in damage to the compact motor-compressors and/or components thereof (e.g., insulation of the stators). Additionally, increased temperatures resulting from the improper management of the heat may cause the bearing system to fail, which may cause the rotary shafts supported by the bearing system to fall or drop onto adjacent mechanical surface. Static and dynamic radial and thrust forces acting on the falling rotary shafts upon failure of the bearing system may cause substantial damage to the rotary shafts and/or surrounding components.
In view of the foregoing, some conventional compact motor-compressors may often utilize external pressurization systems driven separately from the motor-compressors to manage the heat. The external pressurization systems may circulate a separate cooling fluid (e.g., air) in a cooling circuit with an external fan or blower driven independently from the motor-compressors. Failure of the external pressurization systems, however, may result in overheating and potential catastrophic failure. For example, the motor-compressors may continue to operate and generate heat upon failure of the separately driven external pressurization systems, thereby resulting in the overheating of the motor-compressors.
What is needed, then, is an improved cooling system and method for cooling the motor-compressor and/or components thereof capable of operating concurrently with the motor-compressor.